About three quarters of U.S. teens (77%) now have a cell phone. This number is, according to a new report by the Pew Internet & American Life Project, up slightly from September 2009 (75%). Looking back to 2004, though, it’s clear how this number has increased dramatically over the last few years. In late 2004, only 45% of teens had cell phones. The interesting trend here, though, is that 80% of older teens (14-17) now own mobile phones (and 31% of these older teens own smartphones), but that the number of younger teens with cell phones has actually dropped a bit (57% vs. 66%).

Unsurprisingly, teens from households with a higher income are more likely to own cell phones and while 83% of suburban kids now own a mobile phone, only 69% of kids in urban areas and 73% in rural areas own one.

The Pew study did not find a statistically relevant difference between boys and girls when it comes to cell phone ownership, but when it comes to texting, girls are still far heavier users than boys. The median number of texts per girl in this study was closer to 90, while boys only send about 50 (the mean numbers, it’s worth noting, are far higher and also far closer to each other: 165 for girls and 168 for boys). Unsurprisingly, those teens who send the most texts are also more likely to own a smartphone.

As for old-fashioned voice calls, teens – just like the rest of us – are slowly making fewer calls and most teens report that they mostly use text messages to socialize with the people in their lives:

A few days ago, Ubuntu announced its plans to marry its full desktop operating system with the Android mobile operating system. Ubuntu, of course, is mostly known for its Linux distribution, but the company has recently also branched out into consumer electronics with its Ubuntu for TV initiative. Today, we got a chance to spend some hands-on time with the first prototypes of Ubuntu for Android. While it's still obvious that this is a prototype, it's hard not to be positively surprised by the current state of the project.

Here is how it works in practice – and this is a bit similar to the experience with a Motorola Atrix: when you use your phone on the road, it's a regular Android phone. For the most part, you wouldn't even know that it is running Ubuntu as well. When you plug it into its base station however, it becomes a full-blown desktop system that you control with a mouse and keyboard. It even runs Ubuntu TV as well.

A Need for More Speed

The prototypes Ubuntu is using to demonstrate the operating system aren't among the fastest. It takes a little bit before applications like Chrome start up, for example. Ubuntu is quite aware of this, of course, and expects that the first phones with the operating systems will use faster, multi-core processors with more RAM than its current prototypes.

Once your applications are running, though, the desktop feels sufficiently speedy. Maybe the coolest feature of the desktop, though, as that you still have access to the full Android OS, too. You can still make calls, use Google Maps or any other app that runs on the phone. This isn't some emulator either. All the apps still run natively.

Ubuntu hasn't announced any partners yet that will manufacture the phone, but an Ubuntu representative told me that a number of top-tier manufacturers have already approach the company since it first announced this project a few days ago.

More Than a Gimmick

Going into the demo, I couldn't help but think that this was mostly going to be a gimmick, but after seeing the product in action, it does feel like the Ubunut team is on the right track. Chances are, your phone will never be as fast as that multi-core (but also power-hungry) desktop under your desk, but most users never really tap into this power anyway.

Ubuntu is aiming this feature at high-end users for now, but one could also imagine this as a smart solution for developing countries where phones are often peoples' only way of getting online.

Opera just announced the next version of its mobile browser for Android and Symbian, as well as a developer version of its more stripped-down Opera Mini browser. While the update doesn't feature any major changes in the user interface, the Opera team has made numerous changes underneath the surface. Most importantly, Opera added support for its advanced HTML5 parser Ragnarok, which should make running web apps on your mobile phone quite a bit faster. This will also allow developers to create more sophisticated web applications that can run in your phone's browser.

Another feature that should speed up the browsing experience is Opera's newly announced support for using your phone's or tablet's graphics hardware to accelerate 3D content in your browser.

In addition, Opera added support for using an Android device's camera in the browser, as well as support for web standards like CSS3 and CORS.

Even if you don't own an Android or Symbian phone, you will soon be able to use Opera's web-based and desktop emulators to try it out yourself. If you have Opera 12 installed on your phone or tablet, also have a look at the company's demo site.

Opera Mini: Version 7 for iOS and a New Developer Version

As for Opera Mini, Opera today launched the final version of Opera Mini 7 for iOS, as well as a developer version – Opera calls these 'Opera Next.' The Next version is Opera's way of beta testing new features before they are officially released. So if you want to get an early look at some of the browser's features (this version brings smoother scrolling and a new bookmarking interface, for example, give Opera Mini Next a try. It's available for feature phones using Java, as well as Android, Blackberry and S60 phones.

When it comes to using text messaging, Americans used to lag behind the rest of the world. Now, however, it looks as if U.S. cell phone owners are doing their best to catch up with other nations. According to a new PEW Internet and American Life Project study, 73% of all adults in the U.S. who own a cell phone (that’s 83% of all adults, by the way) now use text messaging. Among those, 31% prefer texting over making voice calls (I definitely fall into that category). Unsurprisingly, a higher percentage of those who text the most also tend to prefer texting over voice calls. Overall, though, the growth in the number of average texts send per adult (41.5) is slowing after a major growth boom between the Fall of 2009 and the Spring of 2010 (29.7 to 39.1).

Younger and Older Adults Turn to Text Messaging

There is a clear delineation between how often young adults and older users utilize their text messaging plans, though. The actual numbers for adults between the ages of 18 and 24 are actually quite staggering: they reportedly send 3,200 text per month on average and clearly skew the average number in this study. Virtually all the younger users (95%) in this survey use text messaging on their phones.

It’s not just the younger adults who use SMS. Even those over 35 still send close to 26 messages a day on average (here, too, the most active users are skewing the numbers – the median is 10) and even those over 65 still send 4.7 SMS messages per day (median of 2).

It’s worth noting, though, that these numbers are self-reported (do you know exactly how many messages you sent last month?). Overall, self-reported data is often somewhat unreliable, so I would take this data with a grain of salt. What’s clear, though, is that texting is about as mainstream as it gets today, but it’s definitely not growing as rapidly as it was just a year ago.

When it comes to the radiation that emanates from cell phones, nobody really knows if it is harmful or not. For every study that “proves” that cell phones will cause you cancer, another one appears that shows just the opposite. The Board of Supervisors of San Francisco, though, isn’t going to leave anything to chance and retailers in the city will now have to provide shoppers with information about potential radiation risks.

The version of San Francisco’s cellphone ordinance that passed today is significantly weaker than another one the city tried to pass last year. At that time, though, the wireless industry association CTIA challenged that ordinance in court where it remained in legal limbo until today. The old version would have forced retailers to make comparisons between different phones available to consumers, while the new version just expects them to display general information and to offer a tip sheet on how to reduce (the purported threat of) exposure.

These new rules still have to pass a final vote by the board on July 26, but, according to the Bay Citizen’s Stephanie Sara Chong the general expectation is that the ordinance will easily pass.

No matter what phone you have and whether you have a data plan or not, Skype now lets you make international calls with just a few clicks and from any phone (after a quick setup).

For quite a while now, Skype has been offering Skype to Goas an easy and cheap way to make calls from any phone to your friends, family members and business contacts abroad, but the system wasn’t very flexible (you only got one dial in number) and not necessarily the easiest to use (you had to wade through quite a few voice prompts before you could make your call).

Now, with the new and enhanced Skype to Go, you can now set up a maximum of 9 local direct dial numbers that you can save in your contacts list and that automatically route your calls to your contacts abroad. Skype basically converts your international numbers into local ones.

The great thing about this new feature is that it works from any phone, on any network and doesn’t even eat into your data plans.

If you regularly call your brother in Spain, for example, Skype will give you a local number in the U.S. for him that you can save in your contacts list and whenever you feel like chatting with him, you just dial the local number, type in your pin and Skype will automatically route this call to his number in Spain. You pay Skype’s low international rates for these calls, as well as whatever your landline or mobile phone company charges you for local calls.

To set this up, you sign in to Skype on its website, tell Skype which number to call and it will generate a local number for you (you can choose area codes etc. yourself). Then, you save this local number in your contacts and you’re done.

Opera, the Norwegian browser developer, just announced a touch-optimized version of its browser that it will demo at CES. This new browser, which is optimized for tablets and netbooks with touchscreens. In its demo, Opera is showing off a first demo of the software on an Android device.

Details about the new browser are quite sparse and the demo doesn’t offer any additional details, but it’s good to see that the company is investing in this market as well. Opera already has lots of expertise in developing for touch-enabled phones, so making the move to tablets is a logical next step.

According to Christen Krogh, the company’s chief development officer, “In 2011, tablets are a new must-have. […] Opera for tablets brings the same trusted Internet experience to tablets and netbook PCs as users have come to love on their mobile phones and desktops.”